1. Field of the invention
The present invention relates to a golf club set comprising plural golf clubs of which the lofts are increased in a predetermined order.
2. Description of the Prior Art
Generally, each of the conventional golf club sets consists of a set of wood clubs and a set of iron clubs. The set of woods includes usually five kinds numbered 1 to 5, while the set of irons generally contains seven kinds numbered 3 to 9 and two kinds of utility irons, called wedges (pitching and sand wedges) as well (namely, 9 kinds of irons in total). Generally, these clubs in a set differ from one another in length, loft, lie, head weight, depth of center of gravity, sole area, moment of inertia around the head's center of gravity and flexure of shaft, and the player selects an optimum one of the clubs in his set according to his intended trajectory and carry of the ball he is going to strike with the club. The wood clubs in a set are of a same structure and made of a same material, and the iron clubs in a set are also of a same structure and made of a same material.
The important factors on which the carry and trajectory of a struck ball depend are the height and depth of the center of gravity of the club head. It is generally considered that the ball can be easily propelled higher when struck with a club of which the center of gravity is low, and the ball can be more easily spinned when hit with a club having a deeper center of gravity, also resulting in a high flight of the ball. However, the golf club set consisting of the conventional woods in a set which are of a same structure and made of a same material, combined with irons in a set also of a same structure and material has a gap in depth and height of the center of gravity between these sets so that there is a gap in carry and trajectory of the ball between the sets. The reference numeral 100 in FIGS. 8 to 11 indicate the curves representative of the relations between the depth of the club head's center of gravity and the angle of club face's loft, the height of the center of gravity and the angle of loft, the carry of a struck ball and the angle of loft, and between the angles of elevation and loft, respectively, of the conventional set of wood clubs and the reference numeral 101 indicate such curves of the conventional set of iron clubs. As apparent from these curves, there is a gap or discontinuity between the sets of woods and irons.